For me its Jersey Giants!
I paid a bunch of money to have 8 shipped from a well known breeder and hatched and raised 2 others to add to the group. They got the same attention and care as all my other chickens, yet they are the most skittish and flighty of all that I have. My bantams and layers will eat out of my hand, jump up on me, follow me around, etc. Not the JGs, they run into the coop when you go into the run and out into the run when you go into their coop. I don't know what their problem is, but if they weren't the breed my husband wants, I would have sold them already. I sure hope they calm down when they mature...they are 7 months old now.
Sebrights are another breed I won't ever have again. The girls are skittish and the boys are floggin' little freaks!
Not real thrilled with Wyandottes either at this point. I have a young SL and GL that are very standoffish and the BLRW hates to be touched. Time will tell if they remain here.